Social networking works when the network is small and smart. The moment it grows unmanageable to limits of human cognition (what do you really do with 2.359 contacts?!? Can you remember your common history with no. 1.703?) and quality plummets below mediocre all the networking effect wears off.
Flickr was cool when there was just trannyflickr with Miss K and Erika Baarova (ok perhaps a couple others too :), and it was a privilege to join. Now every picture gets ten invites "Add to my 'Blondes wearing pink lipstick and high heels while sitting on sofa' -group!".
I've read bright opinions how all this false "being connected 24/7 and having hundreds of friends all over the world" is actually worsening the quality of our social lives and more importantly prevents us to focus on anything, be it work, family, hobby, or a real social life. I strongly believe in the referenced fact that being good in anything requires long-spanning concentration more than anything. Would we have the relativity theories if Einsten Twittered his daily minutes of life? I give you Kathy Sierra, I really recommend reading it. And she wrote it two years ago!
"Coffee with your next-door neighbor could do more for your brain than a thousand Twitter updates."
To prove my point, take a look at this monster. Inspiration for this post and a picture from www.ping.fm that enables you to send your status messages from web/mobile/social sites to all the major social networking sites. God bless us from the minor.
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I'll go make a coffee and concentrate on my work.